The Madrid metropolitan area is a monocentric metropolitan area in the centre of the Iberian peninsula, around the city of Madrid, Spain. It is not related to any sort of administrative delimitation, and thus, its limits are ambiguous. According to Populationdata.net it has an estimated 2017 population of 6,321,398 people and covers an area of 5,335.97 square kilometres . It is considered the largest metropolitan area in Spain, the 3rd largest in the European Union and the 54th largest in the world.As with many metropolitan areas of similar size, two distinct zones of urbanisation can be distinguished: Inner ring : Alcorcón, Leganés, Getafe, Móstoles, Fuenlabrada, Coslada, Alcobendas, Pozuelo de Alarcón, San Fernando de Henares Outer ring : Villaviciosa de Odón, Parla, Pinto, Valdemoro, Rivas-Vaciamadrid, Torrejón de Ardoz, Alcalá de Henares, San Sebastián de los Reyes, Tres Cantos, Las Rozas de Madrid, Majadahonda, Boadilla del Monte, Collado Villalba.The largest suburbs are to the south, and in general along the main routes leading out of Madrid. The GDP of the metropolitan area of Madrid was estimated to be 189 billion euros in 2009 and represents over 90% of the GDP of the region of Madrid. The GDP per capita was 37,758 euros in the metropolitan area while it reached 30,453 euros for the Madrid region.